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Construction workers in Edmonton discover dinosaur bones

A construction site in Edmonton is the centre of a significant paleontological study after a worker on a sewage tunnel project uncovered a dinosaur tooth.

A construction site in Edmonton is the centre of a significant paleontological study after a worker on a sewage tunnel project uncovered a dinosaur tooth.

“The tunnel supervisor, Grant Fox, came to my office and told me they found a bone,” said City of Edmonton acting general supervisor of tunneling Yin Hsung.

“I went to the site immediately and talked to Aaron and Riley, who were very thrilled and excited to find the bone. They are part of our team.”

Aaron Krywiak and Ryley Paul were 30 metres underground working on a sewage and flood mitigation tunnel in west Edmonton on Aug. 18, when they saw what might be a dinosaur bone.

They stopped work on the five foot wide by eight foot high tunnel and reported the discovery to their supervisor.

“They found a tooth on Aug. 17. It was kept it in the manager’s office on site, while they waited to see what else might be found,” said Hsung.

“We found quite a few more bone pieces the next day at about 10 a.m. and made a call to the police around 11 a.m.”

Hsung said the police arrived later that afternoon because the call wasn’t considered an emergency.

The police determined the bones weren’t human or suspicious and phoned the Royal Alberta Museum.

Jack Brink, the curator of the museum, visited the site.

Brink is an archeologist and not a paleontologist, but he was certain they found dinosaur bones.

He determined the bones were a well-preserved tooth of a tyrannosaurid (likely Albertosaurus) and large limb bone pieces possibly from the hadrosaur Edmontosaurus.

The find was investigated at the tunnel face by Brink and Mike Burns, a PhD student in paleontology from the University of Alberta.

They discovered more dinosaur bones, including a vertebra and a femur.

“We will work with the U of A palaeontologists to ensure there is someone on site as the material is uncovered so the fossils are preserved without causing any project delays for the city,” said Andrew Neuman, executive director of the Royal Tyrrell Museum.

“The City of Edmonton should be commended for doing the right thing. This is a great example of how we can all work together to preserve Alberta’s heritage.”

The bones are currently being excavated under the supervision of Burns and then transported to the Royal Tyrrell Museum for further study.

Another tooth was discovered and more bones were later found.

The teeth belong to a meat eating dinosaur and the bone to a plant eating one.

They are about 70 million years old and belong to three individuals from two different dinosaur families.

The members of the tunnel excavation team have proven themselves to be extremely qualified to undertake a palaeontological dig, which is a process of dislodging the fossils imbedded or buried in the ground or rock face.

Hsung said sewage tunnel excavation is guided by a surveyor, who initially instructs the team on where to drill the tunnel shaft.

Once the vertical shaft is supported by steel ribs and a timber lining, workers use a jack hammer to loosen up the soil and open up the tunnel horizontally.

Steel ribs and timber are also used to support the ceiling and walls then the whole tunnel will be lined with concrete.

The tunnel is shoveled from the top down, with the soil being shoveled to the floor of the tunnel.

The soil is put into electric train cars and removed.

According to Burns, there is an extremely hard layer above the bones and below there is a layer of soft clay.

The critical layer is about 2 feet above the floor of the tunnel. Burns visits the site daily and stays for a few hours to observe the excavation.

This type of excavating requires a special permit, which is available only to professional palaeontologists.

The tunnel construction team also includes a crane operator, who transports workers and material in and out of the tunnel.

A signal operator makes sure that everybody working in the tunnel is safe.

Another critical aspect of this project is the installation of an electrical and mechanical system, which includes lights, an air compressor to supply air, ventilation fans, pumps, hose and a water supply.

Edmonton’s design and construction department have a lot of experience and expertise in digging tunnels.